Tahoe Backcountry Snow

0400 wx. at 6350′ in Carnelian Bay: 20.1° / 18.0° dew point / 91% RH / mostly clear skies / calm winds / 13″ total storm accumulation 3/31-4/2

0515 wx. at 8650′ Mt. Rose backcountry TH: 11° / mostly clear skies / calm winds

0615 wx. at 9200′ in Mt. Rose backcountry: 17.5° / 12.1° dew point /82.9% RH / clear skies / calm winds / 18-24″ settled new snow above 3/29 crust

Backcountry obs.:

This week’s storms brought more than a refresh to the Tahoe backcountry. Since Mon (3/31) heaps of fresh, cold powder have fallen from the heavens, transforming the previously worn and scratchy snowscape into the pristine winter playground of cold smoke, fluffy soft turns, and face-fulls of powder that has been so hard to come by this season. Snow began on 3/30 and fell in earnest on 3/31 and 4/1, then tapered to light showers and cold temps for 4/2. In total, the backcountry received between 3-4’+ with highest amounts along the Sierra Crest.

Even though the storm was cold, high winds and density changes in the new snow created wind and storm slabs Mon and Tues. A tour Mon (3/31) in the Mt. Rose backcountry revealed a touchy snowpack with multiple skier triggered avalanches noted in wind-loaded zones and sheltered N facing terrain. Click here for a first hand observation.

A dawn tour today (4/3) revealed a largely settled and right-side up snowpack. N and NE aspects host cold, light powder adorning the top 8″, with slightly higher density new snow beneath. Prestorm crusts were between 18-24″ deep, imperceptible while skinning or skiing. Very little wind effect exists on the surface. E-S-NW aspects now hold a fragile, breakable suncrust around 2-3″ thick that’s surprisingly friendly to ski, but far inferior to the cold snow on due N and NE aspects where skiing is pure bliss.

High quality spring powder should hold on at the highest elevations and in the shadiest aspects through today, while solar aspects will quickly begin transitioning to hot pow and suncrust by day’s end.

Weather and forecast thoughts:

Today marks the pendulum shift from winter cold and snow to warm temps and sunshine for the foreseeable future. Enjoy the powder while you can.

Cold temps left in the wake of this week’s storms will moderate a bit today under partly sunny skies. Temps in lower elevation backcountry zones near 7000′ may flirt with freezing this afternoon, while higher areas warm into the upper 20s to low 30s. A few clouds and lingering snow showers will develop this afternoon in response to light afternoon convection across the mountains, but any accumulations will be trivial.

Tonight will be cold, clear, and dry with lows in the 10s and low 20s across the backcountry. Mild inversions may develop by dawn with areas of freezing fog and surface hoar in valleys and depressions.

Tomorrow (4/4), temps will begin warming under mostly sunny skies as a ridge of high pressure builds in to our north. Expect highs reaching the mid 30s across the backcountry, and snow beginning its transition from cold and fluffy to creamy corn, but it’ll take a few days of sun and melt freeze conditions to get there. Beware of the interregnum.

This weekend (4/5-4/6) temps will climb a few degrees higher to near normal values with highs in the low to mid 40s during the day with 20s at night under mostly clear skies. Good corn cultivation weather.

Early next week, models suggest a shortwave trough may brush by the Sierra bringing a pause to the warmup, increased winds and cloudiness, and possibly a shower or two, mainly from Tahoe north. Temps will remain near normal with highs in the 40s and lows in the upper 20s to low 30s.

As the week progresses, temps look to continue their upward march under sunny spring skies with no storms on the horizon.

Time to grab the sunscreen, Hawaiian shirts, and sweat bands. Spring’s coming.

0700 wx. at 6350′ in Carnelian Bay: 25.2 °/ 20.3° dew point / 82% RH / Mostly clear skies / trace new snow

Backcountry obs.:

The recent return to cold and unsettled weather has brought a few inches of new snow to backcountry locations, buffing out surfaces and improving skiing. New snow amounts have been very localized, but areas along the crest picked up between 3-6″ since the pattern change on Thurs (3/27), with lesser amounts in the Mt. Rose area.

Touring in the Mt. Rose backcountry on Fri (3/28), revealed a refrozen spring snowpack with 1-3″ of freshly fallen, cold snow. The new snow smoothed out crusty imperfections, creating dust on crust conditions. Pockets of soft, smooth skiing are available to the most perceptible skiers who sniff out wind deposits in lee areas.

In wind scoured areas, recent cold temps and wind have refrozen the base, into a stiff, yet brittle and edgeable surface. Refrozen crusts should soften this afternoon on southerly aspects providing buttery spring skiing.

Weather and forecast thoughts:

The Tahoe Sierra is currently locked into a cold, unsettled, spring pattern bringing periods of snow and wind, cool temps — and even breaks of brilliant sunshine — lasting well into the first week of April. By the middle of next week, new snow accumulations of 1-2+ are likely throughout the Tahoe backcountry.

The remainder of this afternoon will feature mostly sunny skies with calm to light SW winds and highs reaching the upper 20s to low 30s above 7000′. Shady aspects should still hold soft snow, while southernmost exposures should soften providing good spring skiing. Any breezes that do develop will likely keep crusts hard and frozen.

The next wave of snow moves into the area tomorrow morning (3/30) as a trough of low pressure settles in off the PacNW coast, sending a couple of cool disturbances into the Sierra Sun – Tues (3/30 – 4/1). Increasing SW winds, and a return of widespread snow showers will announce the storm’s arrival. By late afternoon tomorrow, expect on and off snow showers, possibly mixing with rain at lower elevations, and blustery conditions across the mountains. Highs tomorrow will top out in the low to mid 30s across the backcountry.

Snow showers and cold temps will continue Sunday night with an additional 3-6″ possible. Lows Sun night will bottom out in the mid-upper 20s.

Monday (3/31), a more substantial wave of instability moves in, creating heavier and more persistent snow showers throughout the day. Some snow showers may be particularly heavy in the afternoon as convective energy lends an additional kick to atmospheric instability. Snowfall rates could reach 2″ per hour in localized zones, especially over higher terrain. Temps on Mon will remain cool and below freezing above 7000′. By nightfall, another 8-14″ of new snow will likely have fallen across the backcountry.

Mon night accumulating snow showers continue across the Sierra with cold overnight low temps in the 10s and low 20s. Another 3-6″ of cold, fresh snow could continue falling during the overnight hours.

April kicks off on Tues (4/1) with another impulse keeping snow showers firing throughout the day and into the afternoon with moderate accumulations likely. Highs on Tues will remain cold, allowing new snow to continue piling up, before tapering off during the overnight Tues/Weds.

By Weds morning (4/2) the backcountry will likely have received between 1-2’+ of new snow since Sunday. A solid reset, indeed.

The second half of the coming week looks to remain cool and slightly below average, but with lesser chances of accumulating snow. The long wave trough responsible for the coming storm will linger over the Sierra and Great Basin, promoting cold temps, clouds, and daily chances of snow showers across the mountains.

0400 wx. at 6350′ in Carnelian Bay: 37.2° / 34.2° dew point / 89% RH / clear skies

0530 wx. at 8650′ Mt. Rose TH: 37° / clear skies / calm-light SW winds

0630 wx. at 9600′ in Mt. Rose BC: 37.9° / 22.2° dew point / 52% RH / clear skies / light W winds btw 3-5mph

Backcountry obs.:

The recent heat wave bringing high temps in the 40s all the way to 9000’+, along with poor overnight refreezes, has transformed the snow pack into something resembling late spring rather than the first week in March.

This morning I noted weak surface refreezes in open areas below and above treeline. In forested zones, snow surfaces remained punchy and wet with no refrozen crusts.

Tracks, ruts, dinosaur prints, and copious amounts of dog poop tell the tale of heavy usage in the most popular zones, especially late in the day when tracks through hot snow dig too deep to heal with a melt-freeze cycle. Needless to say, the skiing is strenuous and in need of a refresh… and a team of volunteers willing to collect and haul out poop.

But, the exercise and views are as good as ever, now made a bit more joyous by the soundtrack of returning songbirds.

Weather and forecast thoughts:

High clouds and increasing SW winds this afternoon (3/26) are already heralding the end of late spring warmth and a return to colder temperatures and unsettled weather. Models are in strong agreement of a pattern change through the first week of April bringing pulses of low elevation rain and mountain snow. Accumulations look modest with each system, but could provide a round of consecutive surface refreshes for the backcountry over the next 7-10 days.

The first round of rain and snow showers comes in early Thurs. (3/27), lasting through the overnight Fri-Sat (3/28-29). Snow levels will initially start above 8000′ tonight, then fall throughout the day on Thurs, eventually bottoming out below 6000′ Thurs night. Snow levels should remain at or below lake level through Fri (3/26).

Accumulations with this first system will be light (1-3″) below 7000′, with areas near the crest favored for the highest amounts. Above 8000′, 2-6″ are possible.

Sat (3/29) will offer a break in the action with a mix of clouds and sun and cool temps. Highs in the backcountry should reach the mid 30s with lows on Sat night falling into the 20s.

Sun through Tues (3/30 – 4/1) another system could return bringing more rounds of snow showers and cool temps to the Sierra. A notably more potent wave is possible in the Mon – Tues time frame which could bring heavier accumulations to backcountry zones, and even some new accumulating snows below 7000′. Models have been inconsistent with the timing of the Mon-Tues wave, so confidence on snow totals and impacts remains low.

The rolling parade of showery, spring shortwaves looks possible through the first week in April.

The season for big dumps is likely behind us, but patterns like this one can still bring fun, powdery mornings and help extend the corn season through the coming month and into May. Despite being on the down slope of ski season, there are plenty of good days ahead, and maybe just a bit more powder.